As an image display apparatus including current-driven light emitting elements, an organic electroluminescent (EL) display (organic EL display apparatus) including organic EL elements is known. Such an organic EL display is excellent in viewing angle characteristics and has the advantage of low power consumption. The organic EL display typically includes a plurality of light emitting pixels arranged in a matrix. Each light emitting pixel includes an organic EL element, a drive transistor for driving the organic EL element, and a selection transistor for switching the state of the light emitting pixel between Selected and Unselected.
A manufacturing process of the organic EL display includes an inspection of an organic EL panel.
The inspection of the organic EL panel includes, for example, a lighting inspection performed to detect and correct luminance unevenness (unevenness in the amount of luminescence) of the organic EL panel after a driver is mounted on the organic EL panel. The luminance unevenness refers to a phenomenon in which, even with the same luminance signal provided to all the light emitting pixels, the light emitting pixels are not uniform in the amount of luminescence and thereby cause unevenness.
In the lighting inspection, the luminance unevenness can be detected by a technique of, for example, actually lighting up the organic panel, photographing this organic EL panel using an imaging device, and calculating luminance values (corresponding to the amounts of luminescence) using the photographed image from the imaging device (see Patent Literature (PTL) 1, for example).
After the detection of the luminance unevenness, the luminance value (corresponding to the amount of luminescence) is used to calculate, for each of the light emitting pixels, a correction amount of the luminance signal to allow the corrected amount of luminescence of the light emitting pixel to be a predetermined amount of luminescence, for example. This can thus reduce the luminance unevenness caused to the assembled organic EL panel. Examples of the predetermined amount of luminescence include a predetermined fixed value and a mean value.